Why does my boyfriend's (previously my) cat lick me when I get on his nerves?

About a month ago my mom said I couldn't keep my cat, Teetoh, so my boyfriend took him in. Teetoh is a very sweet cat who very rarely bites or scratches. However if I start petting him or handling him in a way that gets on his nerves, he'll lick my hand. Whenever he licks me I'll always be like "Ew. Gross kitty kisses." I assume that he does it because of my negative reaction to it in order to get me to stop but what do you think?